Experimental Models Of Epilepsy Research Articles

Neurprotective Role of Amaranthus Dubius on Penicillin Induced Experimental Epileptic Rat Model by Combating the Multineurotransmitter Deficiency

Objective: The study aims to clarify the protective effects of Amaranthus dubius (AD) in penicillin (PCN)-induced experimental epilepsy models in rats. Method: In this study, twenty-four adult male Wistar albino rats, each weighing between 200-250 grams, were utilized. The rats were allocated into four groups: a control group, an Amaranthus dubius (AD) treated control group, a PCN-induced experimental epileptic rat model group, and an AD pretreated PCN-induced experimental epileptic rat model group. All groups were administered a daily oral dosage of 400 mg/kg body weight of AD aqueous leaf extract for fourteen days via an orogastric cannula. For the experimental epileptic model, PCN was injected into designated areas of the somatosensory cortex. On the concluding fifteenth day, subsequently, the rats were humanely euthanized. Tissue specimens from the cerebral cortex (CC), cerebellum (CB), caudate nucleus (CN), pons and medulla (PM), and midbrain (MB) were extracted, measured, and homogenized to facilitate subsequent biochemical analyses. Result: Pretreatment with AD has demonstrated significant changes in the levels of antioxidants and neurotransmitters in the brain. Conclusion: Amaranthus Dubius aids in combating multi-neurotransmitter deficiencies and enhances the body's antioxidant capabilities.

Classification of Current Experimental Models of Epilepsy.

This article provides an overview of several experimental models, including in vivo, genetics, chemical, knock-in, knock-out, electrical, in vitro, and optogenetics models, that have been employed to investigate epileptogenesis. The present review introduces a novel categorization of these models, taking into account the fact that the most recent classification that gained widespread acceptance was established by Fisher in 1989. A significant number of such models have become virtually outdated. This paper specifically examines the models that have contributed to the investigation of partial seizures, generalized seizures, and status epilepticus. A description is provided of the primary features associated with the processes that produce and regulate the symptoms of various epileptogenesis models. Numerous experimental epilepsy models in animals have made substantial contributions to the investigation of particular brain regions that are capable of inducing seizures. Experimental models of epilepsy have also enabled the investigation of the therapeutic mechanisms of anti-epileptic medications. Typically, animals are selected for the development and study of experimental animal models of epilepsy based on the specific form of epilepsy being investigated. Currently, it is established that specific animal species can undergo epileptic seizures that resemble those described in humans. Nevertheless, it is crucial to acknowledge that a comprehensive assessment of all forms of human epilepsy has not been feasible. However, these experimental models, both those derived from channelopathies and others, have provided a limited comprehension of the fundamental mechanisms of this disease.

Circulating microRNAs and isomiRs as biomarkers for the initial insult and epileptogenesis in four experimental epilepsy models: The EPITARGET study.

Structural epilepsies can manifest months or years after the occurrence of an initial epileptogenic insult, making them amenable for secondary prevention. However, development of preventive treatments has been challenged by a lack of biomarkers for identifying the subset of individuals with the highest risk of epilepsy after the epileptogenic insult. Four different rat models of epileptogenesis were investigated to identify differentially expressed circulating microRNA (miRNA) and isomiR profiles as biomarkers for epileptogenesis. Plasma samples were collected on day 2 and day 9 during the latency period from animals that did or did not develop epilepsy during long-term video-electroencephalographic monitoring. miRNAs and isomiRs were identified and measured in an unsupervised manner, using a genome-wide small RNA sequencing platform. Receiver operating characteristic analysis was performed to determine the performance of putative biomarkers. Two days after an epileptogenic insult, alterations in the levels of several plasma miRNAs and isomiRs predicted epileptogenesis in a model-specific manner. One miRNA, miR-3085, showed good sensitivity (but low specificity) as a prognostic biomarker for epileptogenesis in all four models (area under the curve = .729, sensitivity = 83%, specificity = 64%, p < .05). Identified plasma miRNAs and isomiRs are mostly etiology-specific rather than common prognostic biomarkers of epileptogenesis. These data imply that in preclinical and clinical studies, it may be necessary to identify specific biomarkers for different epilepsy etiologies. Importantly, circulating miRNAs like miR-3085 with high negative predictive value for epileptogenesis in different etiologies could be useful candidates for initial screening purposes of epileptogenesis risk.

The Interactions of Resveratrol and Sodium Valproate on Penicillin-Induced Epilepsy Model: Electrophysiological and Molecular Study.

Epilepsy represents the most prevalent chronic neurological disease, characterized by spontaneous recurrent seizures. In experimental epilepsy models created by different methods, resveratrol has been demonstrated to reduce epileptiform activity and exhibit neuroprotective properties. A penicillin-induced model of epileptogenesis was used to investigate the effects of resveratrol and its combination with sodium valproate on epileptiform activity. The study design was an in vivo animal experimental study. Forty Wistar-albino rats were divided into five groups, each with eight rats. The groups are categorized as the saline group, penicillin group (only penicillin), resveratrol group, sodium valproate group, and resveratrol + sodium valproate group. ECoG recording was taken for 180min in all groups and statistically evaluated. GABAα1, mGluR1/mGluR5, NMDAR1 receptor expressions in the hippocampus, and S100B level in serum were measured. The spike frequency decreased statistically to 60th min in the sodium valproate group and 150th min in the resveratrol group. The spike frequency decreased statistically in the 20th min and later measurements of the recording in the resveratrol + sodium valproate group. GABAα1 receptor expression was increased in all groups compared to the penicillin group. mGluR1/mGluR5, NMDAR1 receptor expression was decreased in all groups compared to the penicillin group. Serum S100B level increased in all groups compared to the penicillin group. There was no statistically significant difference in epileptiform activity when resveratrol alone was administered in the penicillin-induced epilepsy model. Resveratrol co-administered with sodium valproate significantly reduced epileptiform activity. Co-administration of the sodium valproate + resveratrol group made the receptor level's highest GABAα1receptor expression at receptors.

Alterations in DNA 5-hydroxymethylation patterns in the hippocampus of an experimental model of chronic epilepsy

Temporal lobe epilepsy (TLE) is a type of focal epilepsy characterized by spontaneous recurrent seizures originating from the hippocampus. The epigenetic reprogramming hypothesis of epileptogenesis suggests that the development of TLE is associated with alterations in gene transcription changes resulting in a hyperexcitable network in TLE. DNA 5-methylcytosine (5-mC) is an epigenetic mechanism that has been associated with chronic epilepsy. However, the contribution of 5-hydroxymethylcytosine (5-hmC), a product of 5-mC demethylation by the Ten-Eleven Translocation (TET) family proteins in chronic TLE is poorly understood. 5-hmC is abundant in the brain and acts as a stable epigenetic mark altering gene expression through several mechanisms. Here, we found that the levels of bulk DNA 5-hmC but not 5-mC were significantly reduced in the hippocampus of human TLE patients and in the kainic acid (KA) TLE rat model. Using 5-hmC hMeDIP-sequencing, we characterized 5-hmC distribution across the genome and found bidirectional regulation of 5-hmC at intergenic regions within gene bodies. We found that hypohydroxymethylated 5-hmC intergenic regions were associated with several epilepsy-related genes, including Gal, SV2, and Kcnj11 and hyperdroxymethylation 5-hmC intergenic regions were associated with Gad65, TLR4, and Bdnf gene expression. Mechanistically, Tet1 knockdown in the hippocampus was sufficient to decrease 5-hmC levels and increase seizure susceptibility following KA administration. In contrast, Tet1 overexpression in the hippocampus resulted in increased 5-hmC levels associated with improved seizure resiliency in response to KA. These findings suggest an important role for 5-hmC as an epigenetic regulator of epilepsy that can be manipulated to influence seizure outcomes.

Cardarin effect on the formation of histopathological and behavioral abnormalities in the lithium-pilocarpine model of temporal lobe epilepsy in rats

Epilepsy is a severe neuropsychological disease accompanied by the development of spontaneous recurrent seizures (SRS) and associated behavioral disorders that are difficult to treat. In recent years, the neuroprotective properties of agonists of peroxisome proliferator-activated receptors (PPAR α, β/δ, γ), nuclear transcription factors involved in the regulation of lipid and carbohydrate metabolism, as well as inflammatory signaling pathways involved in the pathogenesis of epilepsy, have been actively investigated. The neuroprotective properties of PPARγ agonists have been repeatedly described in models of epilepsy; the effects of PPARβ/δ agonists in these models have not been sufficiently investigated. The aim of this work was to study the effects of administering the PPARβ/δ agonist cardarin on the formation of histopathological and behavioral abnormalities in the lithium-pilocarpine model of temporal lobe epilepsy (TLE). The lithium-pilocarpine model is one of the best experimental models of chronic temporal lobe epilepsy. In this study, epilepsy was induced by administration of pilocarpine to male Wistar rats at the age of 7 weeks one day after LiCl injection. Cardarin (2.5 mg/kg) was administered daily for 7 days after pilocarpine, with the first injection one day after pilocarpine injection. Behavioral testing was performed 2‒3 months after induction of the model in the following tests: Open Field, Resident Stranger, New Object Exploration, Y Maze Spontaneous Alternation and Morris Water Maze. Brain sampling for histological studies (assessment of neuronal death, Nissl staining) was performed after the end of behavioral experiments, 95 days after TLE induction. It was shown that untreated rats with TLE exhibited significant hippocampal neuron death and behavioral disorders: increased motor activity, anxiety, memory disorders, research and communicative behavior. Caradrin did not affect the survival rate of hippocampal neurons, but reduced the manifestation of almost all the above-mentioned behavioral disorders, except for hyperactivity. Thus, this study demonstrated the promising use of PPARβ/δ agonists to attenuate the development of behavioral disorders characteristic of epilepsy.

The Purinergic P2X7 Receptor as a Target for Adjunctive Treatment for Drug-Refractory Epilepsy.

Epilepsy is one of the most common neurological diseases worldwide. Anti-seizure medications (ASMs) with anticonvulsants remain the mainstay of epilepsy treatment. Currently used ASMs are, however, ineffective to suppress seizures in about one third of all patients. Moreover, ASMs show no significant impact on the pathogenic mechanisms involved in epilepsy development or disease progression and may cause serious side-effects, highlighting the need for the identification of new drug targets for a more causal therapy. Compelling evidence has demonstrated a role for purinergic signalling, including the nucleotide adenosine 5'-triphosphate (ATP) during the generation of seizures and epilepsy. Consequently, drugs targeting specific ATP-gated purinergic receptors have been suggested as promising treatment options for epilepsy including the cationic P2X7 receptor (P27XR). P2X7R protein levels have been shown to be increased in the brain of experimental models of epilepsy and in the resected brain tissue of patients with epilepsy. Animal studies have provided evidence that P2X7R blocking can reduce the severity of acute seizures and the epileptic phenotype. The current review will provide a brief summary of recent key findings on P2X7R signalling during seizures and epilepsy focusing on the potential clinical use of treatments based on the P2X7R as an adjunctive therapeutic strategy for drug-refractory seizures and epilepsy.

Vitamin D Relieves Epilepsy Symptoms and Neuroinflammation in Juvenile Mice by Activating the mTOR Signaling Pathway via RAF1: Insights from Network Pharmacology and Molecular Docking Studies.

Epilepsy is a common neurological disorder, and the exploration of potential therapeutic drugs for its treatment is still ongoing. Vitamin D has emerged as a promising treatment due to its potential neuroprotective effects and anti-epileptic properties. This study aimed to investigate the effects of vitamin D on epilepsy and neuroinflammation in juvenile mice using network pharmacology and molecular docking, with a focus on the mammalian target of rapamycin (mTOR) signaling pathway. Experimental mouse models of epilepsy were established through intraperitoneal injection of pilocarpine, and in vitro injury models of hippocampal neurons were induced by glutamate (Glu) stimulation. The anti-epileptic effects of vitamin D were evaluated both in vivo and in vitro. Network pharmacology and molecular docking analysis were used to identify potential targets and regulatory pathways of vitamin D in epilepsy. The involvement of the mTOR signaling pathway in the regulation of mouse epilepsy by vitamin D was validated using rapamycin (RAPA). The levels of inflammatory cytokines (TNF-α, IL-1β, and IL-6) were assessed by enzyme-linked immunosorbent assay (ELISA). Gene and protein expressions were detected by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot, respectively. The terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling (TUNEL) staining was used to analyze the apoptosis of hippocampal neurons. In in vivo experiments, vitamin D reduced the Racine scores of epileptic mice, prolonged the latency of epilepsy, and inhibited the production of TNF-α, IL-1β, and IL-6 in the hippocampus. Furthermore, network pharmacology analysis identified RAF1 as a potential target of vitamin D in epilepsy, which was further confirmed by molecular docking analysis. Additionally, the mTOR signaling pathway was found to be involved in the regulation of mouse epilepsy by vitamin D. In in vitro experiments, Glu stimulation upregulated the expressions of RAF1 and LC3II/LC3I, inhibited mTOR phosphorylation, and induced neuronal apoptosis. Mechanistically, vitamin D activated the mTOR signaling pathway and alleviated mouse epilepsy via RAF1, while the use of the pathway inhibitor RAPA reversed this effect. Vitamin D alleviated epilepsy symptoms and neuroinflammation in juvenile mice by activating the mTOR signaling pathway via RAF1. These findings provided new insights into the molecular mechanisms underlying the anti-epileptic effects of vitamin D and further supported its use as an adjunctive therapy for existing anti-epileptic drugs.

Benefits of Combining Antiepileptic Drugs with Vitamin B12 on Redox Balance: Penicillin-Induced Experimental Epilepsy Model.

A combination of antiepileptic drugs and antioxidants may be an effective treatment by restoring the disrupted redox balance and reducing oxidative stress exposure to neurons. This study aims to evaluate the effects of valproate and vitamin B12 on oxidative stress in an experimental epilepsy model induced by penicillin when administered alone or in combination. 35 male Wistar rats were used in this study. The rats were divided into five groups, which were saline group, 1 mg/kg, 2 mg/kg Vit B12 groups and Sodium valproate group Sodium valproate + Vit B12 group. The epileptic activity was induced by 500 IU of penicillin injection. Sodium valproate and Vitamin B12 were administered 30 min after penicillin administration. Electrocorticogram recordings were taken for 2 hours post-treatment and serum parameters were assessed for oxidative stress markers using spectrophotometric method. There is statistically significant difference between the groups in total antioxidant status, total oxidant status, and oxidative stress index value (p=0.013; p˂0.001; p˂0.001, respectively). The valproate+vitamin B12 group showed elevated total thiol and native thiol levels, along with reduced disulphide levels, resulting in the lowest OSI value. These findings suggest the combined treatment effectively reduces oxidative stress. This study provides valuable insights into the antioxidant properties of valproate and vitamin B12, positioning them as potential agents for managing epilepsy. Understanding the efficacy and reliability of antioxidant strategies in epilepsy management could contribute significantly to advancements in epilepsy therapeutics.

Opposing effects of the purinergic P2X7 receptor on seizures in neurons and microglia in male mice

BackgroundThe purinergic ATP-gated P2X7 receptor (P2X7R) is increasingly recognized to contribute to pathological neuroinflammation and brain hyperexcitability. P2X7R expression has been shown to be increased in the brain, including both microglia and neurons, in experimental models of epilepsy and patients. To date, the cell type-specific downstream effects of P2X7Rs during seizures remain, however, incompletely understood. MethodsEffects of P2X7R signaling on seizures and epilepsy were analyzed in induced seizure models using male mice including the kainic acid model of status epilepticus and pentylenetetrazole model and in male and female mice in a genetic model of Dravet syndrome. RNA sequencing was used to analyze P2X7R downstream signaling during seizures. To investigate the cell type-specific role of the P2X7R during seizures and epilepsy, we generated mice lacking exon 2 of the P2rx7 gene in either microglia (P2rx7:Cx3cr1-Cre) or neurons (P2rx7:Thy-1-Cre). To investigate the protective potential of overexpressing P2X7R in GABAergic interneurons, P2X7Rs were overexpressed using adeno-associated virus transduction under the mDlx promoter. ResultsRNA sequencing of hippocampal tissue from wild-type and P2X7R knock-out mice identified both glial and neuronal genes, in particular genes involved in GABAergic signaling, under the control of the P2X7R following seizures. Mice with deleted P2rx7 in microglia displayed less severe acute seizures and developed a milder form of epilepsy, and microglia displayed an anti-inflammatory molecular profile. In contrast, mice lacking P2rx7 in neurons showed a more severe seizure phenotype when compared to epileptic wild-type mice. Analysis of single-cell expression data revealed that human P2RX7 expression is elevated in the hippocampus of patients with temporal lobe epilepsy in excitatory and inhibitory neurons. Functional studies determined that GABAergic interneurons display increased responses to P2X7R activation in experimental epilepsy. Finally, we show that viral transduction of P2X7R in GABAergic interneurons protects against evoked and spontaneous seizures in experimental temporal lobe epilepsy and in mice lacking Scn1a, a model of Dravet syndrome. ConclusionsOur results suggest a dual and opposing action of P2X7R in epilepsy and suggest P2X7R overexpression in GABAergic interneurons as a novel therapeutic strategy for acquired and, possibly, genetic forms of epilepsy.

Green supported of silver nanoparticles on the surface of reduced graphene oxide: Investigation of its anti-epileptic activity on experimental models of epilepsy in mice

This research demonstrated a novel, simple and environmentally safe process for the fabrication of graphene/silver composite using Malva sylvestris flower extract as a capping and reducing agent. Initially, the Malva sylvestris flower was used to make modified reduced graphene oxide that was coated by extract. The phytochemical groups of extract that have poylphenolic function can act as the green reducing agent for capping and reducing Ag ions on the surface of rGO (Reduced Graphene Oxide) to make the desired rGO/M.S./Ag NPs nanocomposite. The FT-IR, TEM, FE-SEM-EDX and XRD results confirmed the successful fabrication of the desired nanocomposite. The efficacy of the rGO/M.S./Ag NPs was first tested using the 6-Hz-induced seizure model. Subsequently, its effectiveness was assessed against maximal electroshock (MES) and pentylenetetrazole (PTZ)-induced convulsions. Additionally, the impact of the potent rGO/M.S./Ag NPs nanocomposite on Gamma amino butyric acid (GABA) levels in the brain was investigated to elucidate its potential mechanism of action. Furthermore, the effective rGO/M.S./Ag NPs nanocomposite underwent an actophotometer test to evaluate its potential to induce deficits in locomotor activity. During the 6-Hz seizure test, the rGO/M.S./Ag NPs nanocomposite demonstrated a significant and dose-dependent reduction in 6-Hz-induced seizures at doses of 30 and 90 µg/kg. Subsequently, the rGO/M.S./Ag NPs nanocomposite was assessed in MES and PTZ models. Interestingly, rGO/M.S./Ag NPs provided substantial and dose-dependent protection against MES (P < 0.01) and PTZ-induced (P < 0.01) seizures in mice. The rGO/M.S./Ag NPs nanocomposite exhibited a notable increase in brain GABA levels (P < 0.01) compared to the control, while showing no significant change in locomotor activity across all tested doses. Notably, a higher dose of rGO/M.S./Ag NPs nanocomposite (90 µg/kg, p.o.) and Diazepam (5 mg/mg, p.o.) completely prevented convulsions in all anticonvulsant tests. These results indicate that the rGO/M.S./Ag NPs nanocomposite possesses significant anticonvulsant properties, with one potential mechanism being the enhancement of GABA levels in the brain.

Gender-related variation expressions of neuroplastin TRAF6, GluA1, GABA(A) receptor, and PMCA in cortex, hippocampus, and brainstem in an experimental epilepsy model.

Epileptic seizures are seen as a result of changing excitability balance depending on the deterioration in synaptic plasticity in the brain. Neuroplastin, and its related molecules which are known to play a role in synaptic plasticity, neurotransmitter activities that provide balance of excitability and, different neurological diseases, have not been studied before in epilepsy. In this study, a total of 34 Sprague-Dawley male and female rats, 2 months old, weighing 250-300g were used. The epilepsy model in rats was made via pentylenetetrazole (PTZ). After the completion of the experimental procedure, the brain tissue of the rats were taken and the histopathological changes in the hippocampus and cortex parts and the brain stem were investigated, as well as the immunoreactivity of the proteins related to the immunohistochemical methods. As a result of the histopathological evaluation, it was determined that neuron degeneration and the number of dilated blood vessels in the hippocampus, frontal cortex, and brain stem were higher in the PTZ status epilepticus (SE) groups than in the control groups. It was observed that neuroplastin and related proteins TNF receptor-associated factor 6 (TRAF6), Gamma amino butyric acid type A receptors [(GABA(A)], and plasma membrane Ca2+ATPase (PMCA) protein immunoreactivity levels increased especially in the male hippocampus, and only AMPA receptor subunit type 1 (GluA1) immunoreactivity decreased, unlike other proteins. We believe this may be caused by a problem in the mechanisms regulating the interaction of neuroplastin and GluA1 and may cause problems in synaptic plasticity in the experimental epilepsy model. It may be useful to elucidate this mechanism and target GluA1 when determining treatment strategies.

Investigation of the Antiepileptic Effect of (R)-(-) and (S)-(+) Carvone in Penicillin-Induced Epileptiform Activity Model

Aim: Epilepsy affects approximately 70 million people worldwide. While many drugs can prevent seizures, they have a limited impact on preventing or curing the disease. In this perspective, natural compounds, especially monoterpenes derived from medicinal plants, have been investigated in epilepsy models, such as carvone (CAR). The principal constituent of peppermint oil, (R)-(-)-carvone (R-CAR), and the primary component in cumin and dill seed oils, (S)-(+)-carvone (S-CAR), find diverse applications in cosmetics, food, and pharmaceutical formulations. This study aims to investigate the antiepileptic effects of the natural compounds S-CAR and R-CAR in penicillin (PEN)-induced experimental epilepsy model in rats.&#x0D; Material and Method: In the research, 91 male Wistar rats were used. The rats were grouped into 3 main groups as common groups, pre-penicillin groups and post-penicillin groups. The main groups were divided into a total of 13 subgroups. Electrocardiogram recording was taken from rats. At the end of the experiment, the latency of the first epileptiform activity (EA), spike-wave frequency (SWF), and spike-wave amplitude (SWA) of the EA were analyzed. &#x0D; Results: S-CAR and R-CAR administered before penicillin prolonged the latency to the onset of the first EA. S-CAR and R-CAR administered before penicillin decreased SWF. 100 mg/kg doses of S-CAR and R-CAR injected 30 minutes after penicillin administration decreased SWF. While 200 mg/kg dose of R-CAR administered before penicillin decreased SWA in a time-dependent manner, 100 mg/kg dose of S-CAR administered after penicillin decreased SWA.&#x0D; Conclusion: These findings indicate that carvone could exhibit both protective and therapeutic effects in the management of epilepsy.

Microglia and infiltrating macrophages in ictogenesis and epileptogenesis.

Phagocytes maintain homeostasis in a healthy brain. Upon injury, they are essential for repairing damaged tissue, recruiting other immune cells, and releasing cytokines as the first line of defense. However, there seems to be a delicate balance between the beneficial and detrimental effects of their activation in a seizing brain. Blocking the infiltration of peripheral phagocytes (macrophages) or their depletion can partially alleviate epileptic seizures and prevent the death of neurons in experimental models of epilepsy. However, the depletion of resident phagocytes in the brain (microglia) can aggravate disease outcomes. This review describes the role of resident microglia and peripheral infiltrating monocytes in animal models of acutely triggered seizures and epilepsy. Understanding the roles of phagocytes in ictogenesis and the time course of their activation and involvement in epileptogenesis and disease progression can offer us new biomarkers to identify patients at risk of developing epilepsy after a brain insult, as well as provide novel therapeutic targets for treating epilepsy.

Dopamine depletion in wistar rats with epilepsy.

The dopamine content in cerebral structures has been related to neuronal excitability and several approaches have been used to study this phenomenon during seizure vulnerability period. In the present work, we describe the effects of dopamine depletion after the administration of 6-hidroxidopamine (6-OHDA) into the substantia nigra pars compacta of male rats submitted to the pilocarpine model of epilepsy. Susceptibility to pilocarpine-induced status epilepticus (SE), as well as spontaneous and recurrent seizures (SRSs) frequency during the chronic period of the model were determined. Since the hippocampus is one of main structures in the development of this experimental model of epilepsy, the dopamine levels in this region were also determined after drug administration. In the first experiment, 62% (15/24) of 6-OHDA pre-treated rats and 45% (11/24) of those receiving ascorbic acid as control solution progressed to motor limbic seizures evolving to SE, after the administration of pilocarpine. Severeness of seizures during the model´s the acute period, was significantly higher in epileptic experimental rats (56.52%), than in controls (4.16%). In the second experiment, the frequency of seizures in the model's chronic phase did not significantly change between groups. Our data show that dopamine may play an important role on seizure severity in the pilo's model acute period, which seems to be due to dopamine inhibitory action on motor expression of seizure.

Aerobic exercise alters DNA hydroxymethylation levels in an experimental rodent model of temporal lobe epilepsy

The therapeutic potential of aerobic exercise in mitigating seizures and cognitive issues in temporal lobe epilepsy (TLE) is recognized, yet the underlying mechanisms are not well understood. Using a rodent TLE model induced by Kainic acid (KA), we investigated the impact of a single bout of exercise (i.e., acute) or 4 weeks of aerobic exercise (i.e., chronic). Blood was processed for epilepsy-associated serum markers, and DNA methylation (DNAme), and hippocampal area CA3 was assessed for gene expression levels for DNAme-associated enzymes. While acute aerobic exercise did not alter serum Brain-Derived Neurotrophic Factor (BDNF) or Interleukin-6 (IL-6), chronic exercise resulted in an exercise-specific decrease in serum BDNF and an increase in serum IL-6 levels in epileptic rats. Additionally, whole blood DNAme levels, specifically 5-hydroxymethylcytosine (5-hmC), decreased in epileptic animals following chronic exercise. Hippocampal CA3 5-hmC levels and ten-eleven translocation protein (TET1) expression mirrored these changes. Furthermore, immunohistochemistry analysis revealed that most 5-hmC changes in response to chronic exercise were neuron-specific within area CA3 of the hippocampus. Together, these findings suggest that DNAme mechanisms in the rodent model of TLE are responsive to chronic aerobic exercise, with emphasis on neuronal 5-hmC DNAme in the epileptic hippocampus.

ULTRASTRUCTURAL CHANGES OF THE PINEAL GLAND IN EPILEPSY

Circadian mechanisms modulate neuronal excitability at several levels, and their destruction can cause excessive uncontrolled excitability. Previous studies have shown that epilepsy is associated with melatonin levels. Melatonin is a powerful chronobiotic secreted from the pineal gland; helps to maintain normal circadian rhythms and is used to treat some neurological and psychiatric disorders. Circadian rhythms and sleep/wake mechanisms play role in the epilepsy. Melatonin deficiency can decrease seizure threshold, and hence could increase seizure activity. The aim of the study was to identify ultrastructural changes in the pineal gland in an experimental model of epilepsy. Materials and methods. The experiment was carried out on Wistar rats, 5-6 months of age, weight of about 200 g, 36 experimental and 10 control animals. Electrically provoked experimental epileptic seizures model in rats was reproduced. The rats developed spontaneous generalized seizures after 9-14 stimulations. Material for histological examinations was taken after stable formation (for &gt;1 month) of repeated seizures. Ultrathin sections, after contrast with Reynolds lead citrate, were studied under an electron microscope at an accelerating voltage of 75 kV. The increase was selected adequate to the study and ranged from 20,000 to 60,000 times. Results. Experimental studies have confirmed the presence of stable dystrophic, up to apoptosis of some cells, morphological changes of the pineal gland in the experimental model of epilepsy in rats, which is the reason for the decrease in its functional activity. Conclusions. Our experimental data on the morphological changes of the pineal gland confirm the conclusion about a stable, possibly irreversible, decrease in gland function in epilepsy due to damage and disruption of the structure of its cells. Given the polyfunctionality of melatonin, its deficiency can be one of the causes of changes in neural networks, impaired permeability of synaptic membranes, and as a consequence, increased epileptic activity of neurons.

Nesfatin‑1 exerts anticonvulsant effect by reducing oxidative stress in experimental epilepsy model.

Neuropeptides play an important role in the pathogenesis of epilepsy. In the present study, the effect of nesfatin‑1, a neuropeptide, was investigated on penicillin‑induced epilepsy model. Epileptiform activity was induced by an injection of penicillin into the somatomotor cortex at 56 albino Wistar rats. Nesfatin‑1 (i.c.v.) was administered at five different doses (12.5, 25, 50, 100, and 200 pmol) 30 min after a penicillin administration. Astressin 2B, a corticotropin‑releasing factor (CRF) receptor antagonist, was administered 10 minutes later the effective dose of nesfatin‑1 (50 pmol, i.c.v.). Superoxide dismutase (SOD), glutathione (GSH), glutathione peroxidase (GPx), glutathione reductase (GR) and malondialdehyde (MDA) levels in cerebrum were analysed by ELISA method. Nesfatin‑1, at the doses of 25, 50 and 100 pmol, significantly reduced the frequency of epileptiform activity. However, none of the doses of nesfatin‑1 had any effect on the amplitude of epileptiform activity. Astressin 2B alone did not show any effect on epileptiform activity. In addition, astressin 2B had no effect on the anticonvulsant effect of nesfatin‑1. Nesfatin‑1 (at the doses of 25, 50, 100 pmol) did not alter SOD and GSH levels, but significantly increased the GPx and GR levels. Nesfatin‑1 (at a dose of 50 pmol) significantly decreased the MDA level in the cerebrum. Nesfatin‑1 shows anticonvulsant effect and astressin 2B did not affect the anticonvulsant effect of nesfatin‑1. We suggest that nesfatin‑1 has oxidative stress‑mediated anticonvulsant effect in the penicillin‑induced epileptic activity.

Action of Botulinum Neurotoxin E Type in Experimental Epilepsies.

Botulinum neurotoxins (BoNTs) are zinc endopeptidases produced by the Clostridium genus of anerobic bacteria, largely known for their ability to cleave synaptic proteins, leading to neuromuscular paralysis. In the central nervous system, BoNTs are known to block the release of glutamate neurotransmitter, and for this reason, researchers explored the possible therapeutic action in disorders characterized by neuronal hyperactivity, such as epilepsy. Thus, using multidisciplinary approaches and models of experimental epilepsy, we investigated the pharmacological potential of BoNT/E serotype. In this review, written in memory of Prof. Matteo Caleo, a pioneer in these studies, we go back over the hypotheses and experimental approaches that led us to the conclusion that intrahippocampal administration of BoNT/E (i) displays anticonvulsant effects if prophylactically delivered in a model of acute generalized seizures; (ii) does not have any antiepileptogenic action after the induction of status epilepticus; (iii) reduces frequency of spontaneous seizures in a model of recurrent seizures if delivered during the chronic phase but in a transient manner. Indeed, the control on spontaneous seizures stops when BoNT/E effects are off (few days), thus limiting its pharmacological potential in humans.

Research progress on correlations between trace element levels and epilepsy.

Research investigating the correlation between human trace element levels and disease alterations is growing. Epilepsy, a common nervous system disease, has also been found to be closely related to abnormal levels of trace elements. Studies continue to explore mechanisms of various trace elements involved in epileptic seizures through experimental animal models of epilepsy. Thus, we reviewed the research progress on the correlation between trace element levels and epilepsy in recent years and found that the trace elements most closely related to epilepsy are mainly metal ions such as selenium, iron, copper, zinc, and manganese. These results indicate that the changes in some trace elements are closely related to the increase in epilepsy susceptibility. In addition, after treatment with drugs and a ketogenic diet, the concentration of trace elements in the serum of patients with epilepsy changes. In other words, the abnormality of trace element concentrations is of great significance in the occurrence and development of epilepsy. This article is a literature update on the potential role of trace element imbalance in the development of epilepsy, providing new references for the subsequent prevention and treatment of epilepsy.